ENGINE CONTROL DEVICE AND ENGINE CONTROL METHOD

Abstract

A motor controller is connected to an inverter configured to perform power conversion between DC power and AC power, and controls the inverter based on a carrier frequency and a current command value corresponding to a torque command to control driving of a motor using the AC power. The motor controller includes a command value generator that calculates an inverter energy margin value corresponding to an energy margin of the inverter up to an inverter-limiting temperature, which is a limiting temperature of the inverter, based on a detection temperature of the inverter, and generates a new carrier frequency and a new current command value instead of the carrier frequency and the current command value corresponding to the inverter energy margin value.The inverter is controlled by changing the carrier frequency and current setpoint to the new carrier frequency and current setpoint generated by the setpoint generator to increase the temperature of the inverter.

Description

Technical area

[0001] The present invention relates to an engine control device and an engine control method. background

[0002] In recent years, hybrid vehicles and electric vehicles, in which motors are powered by electric power supplied from secondary batteries mounted on the vehicles, have been widely used. This type of vehicle includes an inverter that performs power conversion between DC power and AC power and drives a motor by controlling the inverter. Then, a refrigerant is used to cool the inverter and motor as a heat source for the vehicle's air conditioning or the like. The refrigerant in this type of vehicle cannot serve as a heat source for air conditioning or the like if the inverter is not warmed up, for example, at the time of vehicle start-up.

[0003] PTL 1 discloses a drive device for a vehicle in which a modulation method of PWM control is changed based on the temperature of an inverter detected by a first temperature detector and the temperature of a motor generator detected by a second temperature detector in an inefficiency control when a state of charge of a battery is equal to or greater than a predetermined value. Citation listPatent literature

[0004] PTL 1: JP 2021-132464 A Overview of the inventionTechnical problem

[0005] The device described in PTL 1 cannot efficiently increase the temperature of the inverter within a limited temperature range. Solution to the problem

[0006] A motor control device according to a first aspect of the present invention is connected to an inverter configured to perform power conversion between DC power and AC power, and controls the inverter based on a carrier frequency and a current command value corresponding to a torque command to control driving of a motor using the AC power. The motor control device includes a command value generator that calculates an inverter power margin value corresponding to a power margin of the inverter up to an inverter-limiting temperature, which is a limiting temperature of the inverter, based on a detection temperature of the inverter, and generates a new carrier frequency and a new current command value in place of the carrier frequency and the current command value corresponding to the inverter power margin value.The inverter is controlled by changing the carrier frequency and current setpoint to the new carrier frequency and current setpoint generated by the setpoint generator to increase the temperature of the inverter.

[0007] A motor control method according to a second aspect of the present invention is for a motor control device that is connected to an inverter configured to perform power conversion between DC power and AC power, and that controls the inverter based on a carrier frequency and a current command value corresponding to a torque command to control driving of a motor using the AC power.The method includes: calculating an inverter energy margin value corresponding to an energy margin of the inverter up to an inverter limiting temperature, which is a limiting temperature of the inverter, based on a detection temperature of the inverter; generating a new carrier frequency and a new current command value instead of the carrier frequency and the current command value corresponding to the inverter energy margin value; and controlling the inverter by changing the carrier frequency and the current command value to the new carrier frequency and the new current command value generated according to the inverter energy margin value to increase the temperature of the inverter. Advantageous effects of the invention

[0008] The present invention enables the temperature of an inverter to be efficiently increased within a restrictive temperature range. Brief description of the drawings [ Fig. 1] Fig. 1 is a system configuration diagram of an engine control device. [ Fig. 2] Fig. 2 is a configuration diagram of a controller. [ Fig. 3] Fig. 3 is a configuration diagram of a loss calculator. [ Fig. 4] Fig. Figure 4 is a configuration diagram of a limiting temperature corrector. [ Fig. 5] Fig. Figure 5 is a configuration diagram of a setpoint generator. [ Fig. 6] Fig. 6 is a configuration diagram of a temperature state determiner. [ Fig. 7] Fig. 7 is a configuration diagram of a switching determiner. [ Fig. 8] Fig. 8 is a diagram illustrating an operation example of a motor control device. Description of the embodiments

[0009] Embodiments of the present invention will be described below with reference to the drawings. The description below and the drawings are examples for describing the present invention and are omitted and simplified where appropriate for clarity of description. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be present singly or in multiples.

[0010] Fig. 1 is a system configuration diagram of an engine control device 1000.

[0011] The motor control device 1000 includes an inverter 100 and a controller 200. The motor control device 1000, which includes the inverter 100 and the controller 200, is mounted in a vehicle such as an electric car or a hybrid car, along with a DC power supply 300 and a motor 400 for driving the vehicle. The motor control device 1000 is connected to the inverter 100, which performs power conversion between DC power and AC power, and controls the inverter 100 based on a current command and a carrier frequency corresponding to a torque command to control the driving of the motor 400 using the AC power.

[0012] Inverter 100 is a power converter that performs power conversion between DC power and AC power. Inverter 100 includes upper and lower arm circuits for three phases. Each arm circuit includes a power semiconductor element for switching and a diode. The power semiconductor element is, for example, an IGBT. The power semiconductor element performs a switching operation in response to a gate signal G output from controller 200. The switching operation of the power semiconductor element causes inverter 100 to convert DC power supplied from DC power supply 300 into AC power and output a three-phase AC power. The three-phase AC power output from inverter 100 is supplied to a winding of motor 400 to drive motor 400. During regenerative driving of the motor 400, the inverter 100 causes the motor 400 to act as a generator and converts AC power from the motor 400 into DC power.This DC power is charged into the DC power supply 300, which is a secondary battery such as a battery.

[0013] The power semiconductor element in the inverter 100 generates heat due to the switching operation, and the temperature of the heat is detected by a temperature detector 101 installed near the power semiconductor element. The detected temperature is output to the controller 200 as the detection temperature It of the inverter 100.

[0014] The motor 400 is provided with a position detector 401 that detects a rotational position θ of the motor 400, and the detected rotational position θ is output to the controller 200. The three-phase AC current between the inverter 100 and the motor 400 is detected by a current detector 402, and the detected current values ​​Iu, Iv, and Iw of the respective phases are output to the controller 200. When the motor 400 is driven, the winding and the like of the motor generate heat, and the temperature of the heat is detected by a temperature detector 403 installed near the winding and the like. The detected temperature is output to the controller 200 as the detection temperature Mt of the motor 400.

[0015] The vehicle is equipped with an air conditioner (not shown) for use in cooling and heating within the vehicle. A refrigerant 500 circulates in the air conditioner. The refrigerant 500 flows through a circulation path also located near the inverter 100 and the motor 400, and heat from the inverter 100 and the motor 400 is transferred to the refrigerant. The refrigerant is then used as a heat source for air conditioning or the like of the vehicle. The refrigerant near the inverter 100 has a temperature detected by a temperature detector 501 installed in the refrigerant circulation path. The detected temperature is output to the controller 200 as the refrigerant temperature R1 of the inverter 100. The refrigerant near the motor 400 has a temperature detected by a temperature sensor 502 installed near the refrigerant circulation path.The determined temperature is output to the controller 200 as temperature R2 of the refrigerant of the engine 400.

[0016] Controller 200 references the current values ​​Iu, Iv, and Iw detected by current detector 402 and the rotational position θ detected by position detector 401, and calculates a voltage command value corresponding to a torque command T* from a higher-level controller (not shown). Then, the gate signal G generated using the voltage command value and the carrier wave is output to inverter 100.

[0017] In response to a warm-up mode command H* from the host controller (not shown) and a vehicle deceleration Vr, the controller 200 changes the carrier frequency and the current setpoint to increase the temperatures of the inverter 100 and the motor 400 within a range that does not reach the limiting temperatures of the inverter 100 and the motor 400. Changing the carrier frequency and the current setpoint causes waste energy in the inverter 100 and the motor 400, and this waste energy is dissipated as heat to the refrigerant. Consequently, the temperature of the refrigerant is efficiently increased when the vehicle interior needs to be warmed quickly, such as when the vehicle is started. The details of the controller 200 will be described later.

[0018] Fig. Figure 2 is a configuration diagram of the controller 200.

[0019] The controller 200 includes a warm-up controller 210, a carrier frequency generator 220, and an inverter controller 230.

[0020] The warm-up controller 210 receives the detection temperature It of the inverter 100, the detection temperature Mt of the motor 400, the vehicle deceleration Vr, the refrigerant temperature R1 of the inverter 100, the refrigerant temperature R2 of the motor 400, and the warm-up mode command H*. The vehicle deceleration Vr is input from the host controller (not shown) during regenerative driving of the motor 400. The warm-up controller 210 also receives the torque command T*, the rotational speed ωr of the motor 400, a carrier frequency fc, and a current command I*. The rotational speed ωr of the motor 400 is calculated by the inverter controller 230 based on the rotational position θ. The carrier frequency fc is generated by the carrier frequency generator 220 described later.Examples of the current command I* include a d-axis current command Id* and a q-axis current command Iq*, which are calculated by the inverter controller 230 based on the torque command T*. These commands are collectively referred to below as the current command I*. The warm-up controller 210 regenerates the carrier frequency fc and the current command I* based on the above-described input and outputs the carrier frequency fc and the current command I* along with a switching signal Ch to the inverter controller 230.

[0021] The carrier frequency generator 220 generates the carrier frequency fc based on the speed ωr of the motor 400, a d-axis voltage command value V d *, a q-axis voltage setpoint V q*, the rotational position θ, a DC voltage value Dv from the DC power supply 300, and the torque command T*, and outputs the carrier frequency fc. The carrier frequency generator 220 receives a signal that is not shown.

[0022] The inverter controller 230 includes a current command generator 231, a dq-axis converter 232, a UVW coordinate converter 233, and a gate signal generator 234.

[0023] The current command generator 231 receives the DC voltage value Dv supplied from the DC power supply 300 to the inverter 100, the rotational speed ωr of the motor 400, and the torque command T*, and converts the received torque command T* into the d-axis current command value Id* and the q-axis current command value Iq*. The current command generator 231 receives a signal other than the torque command T*, which signal is not shown.

[0024] The dq-axis converter 232 converts the current values ​​Iu, Iv and Iw detected by the current detector 402 into a d-axis current value I with reference to the rotational position θ d and a q-axis current value I q The dq-axis converter 232 further converts the d-axis current command value Id* based on the d-axis current value I d into the d-axis voltage setpoint V d * and the q-axis current setpoint Iq* based on the q-axis current value I q into the q-axis voltage setpoint V q* and outputs the command values ​​to the coordinate converter 233. The dq-axis converter 232 receives the d-axis current command value Id* and the q-axis current command value Iq* from the warm-up controller 210. Upon receiving the switching signal Ch from the warm-up controller 210, the dq-axis converter 232 activates the d-axis current command value Id* and the q-axis current command value Iq* received from the warm-up controller 210. If no switching signal Ch is received, the dq-axis converter 232 activates the d-axis current command value Id* and the q-axis current command value Iq* received from the current command generator 231.

[0025] The coordinate converter 233 converts the d-axis voltage setpoint V d * and the q-axis voltage setpoint V q * into voltage command values ​​Vu, Vv and Vw of three phases of the UVW phases and outputs the converted values ​​to the gate signal generator 234.

[0026] The gate signal generator 234 generates a carrier wave with a triangular waveform based on the carrier frequency fc. The gate signal generator 234 further generates the gate signal G containing a PWM pulse by comparing the carrier wave with the voltage commands Vu, Vv, and Vw. The gate signal generator 234 receives the carrier frequency fc from each of the warm-up controller 210 and the carrier frequency generator 220. When it receives the switching signal Ch from the warm-up controller 210, the gate signal generator 234 activates the carrier frequency fc received from the warm-up controller 210. When it does not receive a switching signal Ch, the gate signal generator 234 activates the carrier frequency fc received from the carrier frequency generator 220.

[0027] The warm-up controller 210 includes a loss calculator 211, a limiting temperature corrector 212, a setpoint generator 213, and a switching determiner 214.

[0028] The loss calculator 211 receives the torque command T*, the rotational speed ωr of the motor 400, the carrier frequency fc from the carrier frequency generator 220, and the current command value I* from the current command generator 231. The loss calculator 211 also receives the detection temperature It of the inverter 100, the detection temperature Mt of the motor 400, the refrigerant temperature R1 of the inverter 100, and the refrigerant temperature R2 of the motor 400. Based on the received values, the loss calculator 211 calculates a loss Li of the inverter 100 and a loss Lm of the motor 400 and outputs the losses to the limiting temperature corrector 212 and the command value generator 213. Details of the loss calculator 211 will be described later.

[0029] The restrictive temperature corrector 212 corrects each of a restrictive temperature Ri of the inverter 100 and a restrictive temperature Rm of the motor 400 based on the loss Li of the inverter 100, the loss Lm of the motor 400, the detection temperature It of the inverter 100, the detection temperature Mt of the motor 400, the refrigerant temperature R1 of the inverter 100, and the refrigerant temperature R2 of the motor 400 received, and outputs the corrected values ​​to the setpoint generator 213. The restrictive temperatures Ri and Rm are upper restrictive temperatures at which the inverter 100 and the motor 400 operate, respectively. Details of the restrictive temperature corrector 212 will be described later.

[0030] The setpoint generator 213 receives the detection temperature It of the inverter 100, the detection temperature Mt of the motor 400, the vehicle deceleration Vr, the refrigerant temperature R1 of the inverter 100, and the refrigerant temperature R2 of the motor 400. The setpoint generator 213 further receives the loss Li of the inverter 100 and the loss Lm of the motor 400 from the loss calculator 211, and the restricting temperature Ri of the inverter 100 and the restricting temperature Rm of the motor 400 from the restricting temperature corrector 212. Based on the received values, the command value generator 213 calculates an energy margin value up to the limiting temperature Ri of the inverter 100 and the limiting temperature Rm of the motor 400, generates a new carrier frequency fc and a new current command value I* corresponding to the energy margin value, and outputs the generated values ​​to the inverter controller 230.The newly generated carrier frequency fc and the newly generated current command value I* replace the carrier frequency fc generated by the carrier frequency generator 220 and the current command value I* generated by the coordinate converter 233. The motor controller 1000 controls the inverter by changing the carrier frequency fc and the current command value I* generated by the command value generator 213 according to a condition. The current command value I* is represented by a phase angle of a current and a current magnitude. Details of the command value generator 213 will be described later.

[0031] The switching determiner 214 receives the torque command T*, the rotational speed ωr of the motor 400, the carrier frequency fc from the command generator 213, and the warm-up mode command H*. Based on the received values, the switching determiner 214 determines whether to permit the change in the carrier frequency fc and the current command I* generated by the command generator 213. If it is determined to permit the change, the switching signal Ch is output to the dq-axis converter 232 and the gate signal generator 234. Details of the switching determiner 214 will be described later.

[0032] Although the controller 200 configured with multiple blocks has been described, the controller 200 may be composed of a computer including a CPU, a memory, and the like. In this configuration, the computer performs processing by executing a program stored in a memory or the like. All or part of the processing of the multiple blocks may be implemented by a hard-wired logic circuit. The program may be provided after being stored in advance in a storage medium. Alternatively, the program may be provided via a network line. The program may be provided as a computer program product in which various forms, such as a data signal, can be read by a computer.

[0033] Fig. Figure 3 is a configuration diagram of the loss calculator 211.

[0034] The loss calculator 211 includes loss reference units 2111a and 2111b, time constant calculators 2112a and 2112b, and loss integrators 2113a and 2113b. The loss reference unit 2111a, the time constant calculator 2112a, and the loss integrator 2113a of the loss calculator 211 calculate the loss Li of the inverter 100. The loss reference unit 2111b, the time constant calculator 2112b, and the loss integrator 2113b of the loss calculator 211 calculate the loss Lm of the motor 400.

[0035] The loss reference unit 2111a includes a map m1a corresponding to combinations of a plurality of carrier frequencies fc and a plurality of current command values ​​I*. The map m1a includes, for example, maps for large, medium, and small carrier frequencies fc, respectively, and the maps each include maps for large, medium, and small current command values ​​I*. The three levels of large, medium, and small are examples, and maps of a plurality of levels can be appropriately set depending on the memory capacity of the controller 200 and the like. The map m1a includes a combination of the specific carrier frequency fc and the current command value I*, in which the loss La [W (watts)] per unit time of the inverter 100, which corresponds to the torque and speed of the motor 400, is stored in advance. The map m1a indicates a torque of 0 or less, indicating regenerative driving.The loss reference unit 2111a selects the mapping m1a according to a combination of the received carrier frequency fc and the current command I*, and outputs the loss La [W (watts)] per unit time of the inverter 100 corresponding to a position relative to the input torque command T* and the rotational speed ωr of the motor 400, that is, an operating point a1. Generally, the loss La per unit time of the inverter 100 increases when the carrier frequency is high.

[0036] The time constant time calculator 2112a calculates, from the loss La per unit time, a time until the temperature of the inverter 100 rises and becomes stable, that is, a time constant time ti. A relationship between a value obtained by subtracting the temperature R1 of the refrigerant of the inverter 100 from the detection temperature It of the inverter 100 and the time constant time ti is stored in advance as a map, and thus the time constant time ti corresponding to the loss La per unit time is determined with reference to the map.

[0037] The loss integrator 2113a calculates the loss Li [Wh] of the inverter 100 during the time constant time ti according to equation (1) below, where a current time is indicated as t, based on the loss La (t) per unit time and the time constant ti. [Expression 1] L i=∫t−titLa(t)dt

[0038] The loss reference unit 2111b includes a map m1b corresponding to combinations of a plurality of carrier frequencies fc and a plurality of current command values ​​I*. The map m1b includes, for example, maps for each of large, medium, and small carrier frequencies fc, and the maps each include maps for each of large, medium, and small current command values ​​I*. The three levels of large, medium, and small are examples, and maps of a plurality of levels can be appropriately set depending on the memory capacity of the controller 200 and the like. The map m1b includes a combination of the specific carrier frequency fc and the current command value I*, in which the loss Lb [W (watts)] per unit time of the motor 400 is stored in advance according to the torque and speed of the motor 400.The loss reference unit 2111b selects the mapping m1b according to a combination of the received carrier frequency fc and the current command I*, and outputs the loss Lb [W (watts)] per unit time of the motor 400 corresponding to a position with respect to the input torque command T* and the rotational speed ωr of the motor 400, that is, an operating point b1.

[0039] The time constant time calculator 2112b calculates, from the loss Lb per unit time, a time until the temperature of the motor 400 rises and becomes stable, that is, a time constant time tm. A relationship between a value obtained by subtracting the temperature R2 of the refrigerant of the motor 400 from the detection temperature Mt of the motor 400 and the time constant time tm is stored in advance as a map, and thus the time constant time tm corresponding to the loss Lb per unit time is determined with reference to the map.

[0040] The loss integrator 2113b calculates the loss Lm [Wh] of the motor 400 during the time constant time tm according to the expression (2) below, where a current time is indicated as t, based on the loss Lb (t) per unit time and the time constant time tm. [Expression 2] L m=∫t−tmtLb(t)dt

[0041] Although the time constant times ti and tm are determined by the time constant time calculators 2112a and 2112b, respectively, and the losses Li and Lm are calculated using the time constant time, a predetermined fixed time may be used instead of the time constant times ti and tm.

[0042] Fig. 4 is a configuration diagram of the limiting temperature corrector 212.

[0043] The restrictive temperature corrector 212 includes estimated temperature reference units 2121a and 2121b, differential temperature calculators 2122a and 2122b, and restrictive temperature update units 2123a and 2123b.

[0044] The estimated temperature reference unit 2121a estimates the temperature of the inverter 100 based on the loss Li of the inverter 100 and outputs an estimated temperature Ix. Specifically, a relationship between the temperature Ix of the inverter 100 and a loss [Wh] of the inverter 100 is stored in advance as a map corresponding to a value T1 obtained by subtracting the temperature of the refrigerant of the inverter 100 from the temperature of the inverter 100. The estimated temperature reference unit 2121a adds the loss Li calculated this time to a loss Li' calculated last time, and, with reference to the map, obtains the estimated temperature Ix corresponding to a loss resulting from the addition. The loss is calculated at a time interval equal to or longer than the time constant time ti.The last calculated loss Li' is a loss last transmitted from the loss calculator 211 and stored in the limiting temperature corrector 212.

[0045] The differential temperature calculator 2122a determines whether a differential temperature obtained by subtracting the estimated temperature Ix from the detection temperature It is greater than a predetermined threshold, and passes the differential temperature and a determination result to the limiting temperature update unit 2123a. If the detection temperature It increases from the estimate, the differential temperature increases.

[0046] Upon receiving the determination result indicating that the temperature is greater than the threshold, the restrictive temperature updating unit 2123a subtracts the differential temperature from a last updated restrictive temperature Ri' to lower the restrictive temperature Ri, and outputs the lowered restrictive temperature Ri as a new restrictive temperature Ri. The last updated restrictive temperature Ri' is stored in the restrictive temperature corrector 212. The restrictive temperature Ri has an initial value that is a predetermined upper restrictive temperature at which the inverter 100 normally operates, and the predetermined upper restrictive temperature is set as the initial value of the restrictive temperature Ri when an ignition key of the vehicle is turned on or when the heater of the vehicle's air conditioner is turned on.

[0047] The estimated temperature reference unit 2121b estimates the temperature of the motor 400 based on the loss Lm of the motor 400 and outputs an estimated temperature Mx. Specifically, a relationship between the temperature of the motor 400 and a loss [Wh] of the motor 400 is stored in advance as a map corresponding to a value T2 obtained by subtracting the temperature of the refrigerant of the motor 400 from the temperature of the motor 400. The estimated temperature reference unit 2121b adds the loss Lm calculated this time to a loss Lm' calculated last time and obtains the estimated temperature Mx corresponding to a loss of a result of the addition with reference to the map. The loss is calculated at a time interval equal to or longer than the time constant time tm.The last calculated loss Lm' is a loss last transmitted from the loss calculator 211 and stored in the limiting temperature corrector 212.

[0048] The differential temperature calculator 2122b determines whether a differential temperature obtained by subtracting the estimated temperature Mx from the detection temperature Mt is greater than a predetermined threshold, and outputs the differential temperature and a determination result to the limiting temperature update unit 2123b. If the detection temperature Mt increases from the estimate, the differential temperature increases.

[0049] Upon receiving the determination result indicating that the temperature is greater than the threshold, the restrictive temperature updating unit 2123b subtracts the differential temperature from a last updated restrictive temperature Rm' to lower the restrictive temperature Rm, and outputs the lowered restrictive temperature Rm as a new restrictive temperature Rm. The last updated restrictive temperature Rm' is stored in the restrictive temperature corrector 212. The restrictive temperature Rm has an initial value that is a predetermined upper restrictive temperature at which the engine 400 normally operates, and the predetermined upper restrictive temperature is set as the initial value of the restrictive temperature Rm when the vehicle's ignition key is turned on or when the heater of the vehicle's air conditioner is turned on.

[0050] As described above, when a deviation occurs between the estimated temperature Ix estimated based on the loss Li of the inverter 100 and the detection temperature It of the inverter 100, the restricting temperature corrector 212 updates the restricting temperature Ri of the inverter 100 according to the deviation. When a deviation occurs between the estimated temperature Mx estimated based on the loss Lm of the motor 400 and the detection temperature Mt of the motor 400, the restricting temperature corrector 212 updates the restricting temperature Rm of the motor 400 according to the deviation. Consequently, the calculation accuracy of the energy margin value obtained by the command value generator 213 to be described later is improved.

[0051] Fig. Figure 5 is a configuration diagram of the setpoint generator 213.

[0052] The setpoint generator 213 includes energy span value calculators 2131a and 2131b, setpoint reference units 2132a and 2132b, setpoint selectors 2133a and 2133b, and a temperature state determiner 2134.

[0053] The energy margin value calculator 2131a calculates an energy margin value Wi corresponding to an energy margin to the restricting temperature Ri of the inverter 100 based on the restricting temperature Ri of the inverter 100, the detection temperature It of the inverter 100, the temperature R1 of the refrigerant of the inverter 100, and the loss Li of the inverter 100. Specifically, a relationship between the temperature of the inverter 100 and a loss [Wh] of the inverter 100 is stored in advance as a map for each value T1 obtained by subtracting the temperature of the refrigerant of the inverter 100 from the temperature of the inverter 100, as shown in a graph in the energy margin value calculator 2131a of Fig. 5. The energy margin value calculator 2131a calculates the energy margin value Wi by subtracting the loss Li of the inverter 100 received from the loss calculator 211 from a loss L0 of the inverter 100 corresponding to the restricting temperature Ri, with reference to this map, and outputs the energy margin value Wi to the set value reference unit 2132a.

[0054] The setpoint reference unit 2132a determines a carrier frequency and a current setpoint associated with the energy loss of the inverter 100 based on the energy margin value Wi and the delay Vr. Specifically, the setpoint reference unit 2132a includes a map GIa and a map Gfa corresponding to a plurality of delay degrees Vr. The map GIa prestores a relationship between the amount of energy to be lost by the inverter 100 for each of a plurality of carrier frequencies fc and each of a plurality of current setpoints Iz. The map Gfa prestores a relationship between the amount of energy to be lost by the inverter 100 for each of a plurality of current setpoints I* and each of a plurality of carrier frequencies fz.The values ​​of the mappings GIa and Gfa are determined in advance by a trial calculation based on the torque change up to speed 0 based on the deceleration Vr during the regenerative driving of the motor 400. In addition to the deceleration Vr, the torque change can be estimated by a trial calculation taking into account the load capacity, the vehicle weight, a gradient, and the like.

[0055] In general, energy loss at any torque increases as a carrier frequency increases below a certain current command. For example, the current loss shown in the command reference unit 2132a of Fig. 5, the map GIa has a horizontal axis representing time and a vertical axis representing loss, and shows the amount of energy loss generated at a carrier frequency fc1 in gray as time passes. The map GIa shows a region surrounded by a dashed line, where the region indicates the amount of energy loss generated at a carrier frequency fc2 higher than the carrier frequency fc1, where the amount of energy loss is greater than that at the carrier frequency fc1. The amount of energy loss causes the inverter 100 to generate heat, which is used as a heat source for heating the refrigerant.As shown in the map GIa in the command reference unit 2132a, the command reference unit 2132a stores in advance a relationship between the amount of energy to be lost by the inverter 100 for each of a plurality of carrier frequencies fc and each of a plurality of current command values ​​Iz, and the relationship is stored as a map for each delay Vr.

[0056] Similarly, the setpoint reference unit 2132a in Fig. 5, the map Gfa shown has a horizontal axis representing time and a vertical axis representing loss, and shows, for example, the amount of energy loss generated by a current command value I*1 in gray according to the passage of time. The map Gfa shows an area surrounded by a dashed line, the area indicating the amount of energy loss generated by a current command value I*2 higher than the current command value I*1. As shown in the map Gfa in the command value reference unit 2132a, the command value reference unit 2132a stores in advance a relationship between the amount of energy to be lost by the inverter 100 for each of a plurality of current command values ​​I* and each of a plurality of carrier frequencies fz, and the relationship is stored as a map for each delay Vr.

[0057] The command value reference unit 2132a calculates a combination of a carrier frequency and a current command value with reference to the maps GIa and Gfa, the combination causing the amount of energy loss during the change of loss according to the torque change indicated by the received deceleration Vr to be closest to the energy margin value Wi. For the calculation, combinations of carrier frequencies and current command values ​​include two sets: a p-set when a carrier frequency is changed and a q-set when a current command value is changed. Specifically, the p-set containing combinations of carrier frequencies and current command values ​​is obtained with reference to the map GIa, and the q-set containing combinations of carrier frequencies and current command values ​​is obtained with reference to the map Gfa.The setpoint reference unit 2132a outputs carrier frequencies and current setpoints of the two sets to the setpoint selector 2133a.

[0058] The setpoint selector 2133a selects and outputs one of the combinations of the carrier frequencies and the current setpoints in response to a signal indicating a temperature state from the temperature state determiner 2134, which determines the temperature state of the inverter 100. The setpoint selector 2133a of Fig. Figure 5 shows graphs containing a graph G1 of the carrier frequency and the magnitude of the loss, and a graph G2 of the current command and the magnitude of the loss. The p-set with a relatively high carrier frequency and a relatively low current command and the q-set with a relatively low carrier frequency and a relatively high current command are equal in the magnitude of the energy loss, as long as the sets are equal in terms of torque.

[0059] When the setpoint selector 2133a receives a first temperature state signal S1 from the temperature state determiner 2134, indicating that the inverter 100 or the motor 400 is at a temperature not close to its limiting temperature, it selects and outputs the carrier frequency and current setpoint of the q-set, which has a lower carrier frequency than the p-set and a higher current setpoint than the p-set. Specifically, the carrier frequency is selected within a range of the energy margin value Wi of the inverter 100, and the carrier frequency is higher than a carrier frequency in a normal operation (operation without changing the carrier frequency or current setpoint in the first temperature state S1 to a third temperature state S3).Then, the current command is selected with a low value, where the low value prioritizes increasing loss by shifting the current command from a high-efficiency point over increasing loss by increasing a carrier frequency. Consequently, a carrier frequency and current command at which the loss of the inverter 100 and the motor 400 is maximized can be selected.

[0060] In contrast, when the setpoint selector 2133a receives a second temperature state signal from the temperature state determiner 2134 indicating that the inverter 100 is at a temperature close to its limiting temperature, it selects the carrier frequency and current setpoint of the q-set, which has a lower carrier frequency than that of the p-set and a higher current setpoint than that of the p-set. The selected carrier frequency fc is output to the gate signal generator 234 and the setpoint reference unit 2132b, and the current setpoint I* is output to the setpoint selector 2133b. Specifically, a low carrier frequency within the range of the energy margin value Wi of the inverter 100 is selected as the carrier frequency. This carrier frequency has a value lower than that of the carrier frequency selected in the first temperature state.Then, a combination of a high-value current command and a high-value carrier frequency is selected, which shifts the current command from its high-efficiency point and causes the loss to increase to a maximum. Consequently, a carrier frequency and current command value can be selected that maximize the loss of the motor 400 while limiting the loss of the inverter 100.

[0061] In contrast, when the command selector 2133a receives a third temperature condition signal from the temperature condition determiner 2134 indicating that the motor 400 is at a temperature close to a limiting temperature of the motor 400, it selects the carrier frequency and current command of the p-set with a higher carrier frequency than that of the q-set and a lower current command than that of the q-set. Specifically, when a high carrier frequency within the range of the energy margin value Wi of the inverter 100 is selected as the carrier frequency, the carrier frequency and current command at which the loss of the inverter 100 is maximized while limiting the loss of the motor 400 can be selected.

[0062] The setpoint selector 2133a outputs the selected carrier frequency fc to the gate signal generator 234 and the setpoint reference unit 2132b and outputs the current setpoint I* to the setpoint selector 2133b.

[0063] The energy margin value calculator 2131b calculates an energy margin value Wm corresponding to an energy margin to the restricting temperature Rm of the motor 400 based on the restricting temperature Rm of the motor 400, the detection temperature Mt of the motor 400, the temperature R2 of the refrigerant of the motor 400, and the loss Lm of the motor 400. Specifically, a relationship between the temperature of the motor 400 and the loss [Wh] of the motor 400 is stored in advance as a map for each value T2 obtained by subtracting the temperature of the refrigerant of the motor 400 from the temperature of the motor 400, as shown in a graph in the energy margin value calculator 2131b of Fig. 5. The energy margin value calculator 2131b calculates the energy margin value Wm by subtracting the loss Lm of the motor 400 received from the loss calculator 211 from a loss L1 of the motor 400 corresponding to the restricting temperature Rm with reference to this map, and outputs the energy margin value Wm to the target value reference unit 2132b.

[0064] The target value reference unit 2132b determines a carrier frequency and a current target value associated with the energy loss of the motor 400 based on the energy margin value Wm and the deceleration Vr. Specifically, the target value reference unit 2132b includes a map GIb corresponding to a plurality of degrees of deceleration Vr. The map GIb prestores a relationship between the amount of energy to be lost by the motor 400 for each of a plurality of current target values ​​I* and each of a plurality of carrier frequencies fz. The values ​​of the map GIb are obtained in advance by a trial calculation based on the torque transition up to speed 0 based on the deceleration Vr during regenerative driving of the motor 400. In addition to the deceleration Vr, the torque transition can be estimated by a trial calculation taking into account the load capacity, vehicle weight, a gradient, and the like.

[0065] The setpoint reference unit 2132b of Fig. The map Glb shown in Figure 5 has a horizontal axis representing time and a vertical axis representing loss, and shows the amount of energy loss generated by the current set value I*1 in gray as time passes. Then, a dashed area of ​​the map GIb shows the amount of energy loss generated by the current set value I*2 being greater than the current set value I*1, and the amount of energy loss is greater than that generated by the current set value I*1. This amount of energy loss causes the motor 400 to generate heat, which is used as a heat source to heat the refrigerant.As shown in the map Glb in the command reference unit 2132b, the command reference unit 2132b stores in advance a relationship between the amount of energy to be lost of the motor 400 for each of a plurality of current command values ​​I* and each of a plurality of carrier frequencies fz, and the relationship is stored as a map for each deceleration Vr.

[0066] The command reference unit 2132b calculates a current command with reference to the map GIb, the current command causing the amount of energy loss at the carrier frequency fc output from the command selector 2133a to be within the energy margin value Wm at the change of loss corresponding to the torque change indicated by the received deceleration Vr. In other words, the current command I* output from the command selector 2133a is corrected to cause maximum energy loss, that is, maximum heat generation according to the energy margin value Wm of the motor 400. However, it is desirable to calculate a current command that is within the energy loss of the inverter 100.

[0067] In response to a temperature condition indicative signal from the temperature condition determiner 2134, which determines a temperature condition of the motor 400, the command selector 2133b selects and outputs one of the following: a current command corrected by the command reference unit 2132b, a current command changed to a value lower than the corrected current command, and a current command output from the command selector 2133a.

[0068] Specifically, when no signal of the third temperature condition S3 is input, the signal indicating that the motor 400 has a temperature close to the limiting temperature of the motor 400, or the like, is input, the current command value corrected by the command value reference unit 2132b is selected and output to the dq-axis converter 232. If the corrected current command value is not within the energy loss of the inverter 100, the current command value output by the command value selector 2133a is output.

[0069] When the third temperature state signal S3 is received, the current command value corrected by the command value reference unit 2132b or the current command value output by the command value selector 2133a is changed, for example, to a value obtained by subtracting a predetermined percentage of the current command value from the current command value, and output. Alternatively, the command value reference unit 2132b may decrease the current command value I* and increase the carrier frequency fc output by the command value selector 2133a within a range that is within the amount of energy loss within the energy margin value Wm when the third temperature state signal S3 is received. Specifically, a combination of a current command value and a carrier frequency is selected at which the current command value is low and the loss increase is maximized within a range of the energy margin value Wm of the motor 400.The combination of the current setpoint and the carrier frequency is selected such that the motor 400 is not changed in a torque value, i.e., the motor 400 has a torque that is equal to that before the current setpoint was changed.

[0070] The setpoint generator 213 calculates and controls the carrier frequency and current setpoint that causes a maximum amount of energy loss, preferably for the inverter 100, so that the temperature of the inverter 100, which has a lower heat capacity than the motor 400, can be efficiently increased first.

[0071] An example has been described in which the command generator 213 preliminarily estimates the torque change through trial calculations during regenerative driving of the motor 400 and determines the carrier frequency and current command value associated with the energy loss of the inverter 100 and the motor 400. In addition, the carrier frequency and current command value associated with the energy loss of the inverter 100 and the motor 400 can be determined by preliminarily estimating the torque change through trial calculations during power driving of the motor 400.

[0072] Fig. 6 is a configuration diagram of the temperature state determiner 2134.

[0073] The temperature state determiner 2134 includes temperature rise calculators 2134a and 2134b and a temperature determiner 2134c.

[0074] The temperature state determiner 2134 determines the first temperature state S1 when the restricting temperature Ri of the inverter 100 and the restricting temperature Rm of the motor 400 are not updated, that is, when no deviation occurs in the estimated temperatures Ix and Mx, determines the second temperature state S2 when the restricting temperature Ri of the inverter 100 is updated, that is, when a deviation occurs in the estimated temperature Ix, and determines the third temperature state S3 when the restricting temperature Rm of the motor 400 is updated, that is, when a deviation occurs in the estimated temperature Mx.

[0075] The temperature rise calculator 2134a determines whether a differential temperature obtained by subtracting the most recently updated restrictive temperature Ri' of the inverter 100 from the restrictive temperature Ri of the inverter 100 is greater than a predetermined threshold, and outputs a determination result to the temperature determiner 2134c. The temperature rise calculator 2134b determines whether a differential temperature obtained by subtracting the most recently updated restrictive temperature Rm' from the restrictive temperature Rm of the motor 400 is greater than a predetermined threshold, and outputs a determination result to the temperature determiner 2134c. The most recently updated restrictive temperatures Ri' and Rm' are stored in the temperature state determiner 2134.

[0076] The temperature determiner 2134c determines the first temperature state S1 when none of the temperature rise calculators 2134a and 2134b receives a determination result greater than the threshold. The first temperature state S1 indicates that there is no deviation in the estimated temperatures Ix and Mx of the inverter 100 and the motor 400, and indicates that the inverter 100 and the motor 400 can generate heat at the maximum.

[0077] The temperature determiner 2134c determines the second temperature state S2 when the determination result greater than the threshold is received from the temperature rise calculator 2134a, that is, when the inverter 100 has a temperature close to its limiting temperature. The second temperature state S2 indicates that a deviation occurs in the estimated temperature Ix of the inverter 100, that is, that the temperature rises by more than an estimated temperature rise, requiring that the heat generation of the inverter 100 be reduced. The temperature determiner 2134c determines the third temperature state S3 when the determination result greater than the threshold is received from the temperature rise calculator 2134b.The third temperature state S3 indicates that a deviation occurs in the estimated temperature Mx of the motor 400, that is, the temperature increases by more than an estimated temperature increase, which requires that the heat generation of the motor 400 be reduced.

[0078] When the temperature determiner 2134c receives the determination result greater than the threshold from each of the temperature rise calculators 2134a and 2134b, it determines the second temperature state S2 or the third temperature state S3 according to the result that is closer to the corresponding limiting temperature. Specifically, the second temperature state S2 is determined when the inverter 100 has a temperature closer to its limiting temperature than that of the motor 400. When the motor 400 has a temperature closer to its limiting temperature than that of the inverter 100, the third temperature state S3 is determined.

[0079] The temperature state determiner 2134 can determine the first temperature state S1, the second temperature state S2, or the third temperature state S3 by detecting the detection temperatures It and Mt of the inverter 100 and the motor 400, where the detection temperatures have approached the corresponding limiting temperatures. That is, the first temperature state S1 is determined when the inverter 100 has a temperature not close to the limiting temperature Ri of the inverter 100 and the motor 400 has a temperature not close to the limiting temperature Rm of the motor 400, the second temperature state S2 is determined when the inverter 100 has a temperature close to the limiting temperature Ri of the inverter 100, and the third temperature state S3 is determined when the motor 400 has a temperature close to the limiting temperature Rm of the motor 400.

[0080] Fig. 7 is a configuration diagram of the switching determiner 214.

[0081] The switching determiner 214 determines whether the change in the carrier frequency fc and the current setpoint I* generated by the setpoint generator 213 is permitted. In particular, the Fig. 7 are prestored in accordance with the carrier frequencies fc, the mappings each having a vertical axis representing the torque command T*, a horizontal axis representing the rotational speed ωr of the motor 400, and a region Np shown in gray in which the switching signal Ch is not output.

[0082] The map Gn1 is used when the carrier frequency fc is low and indicates a state where the rotational speed ωr is slow, the torque is large, and ripple of the motor 400 is likely to occur. The map Gn2 is used when the carrier frequency fc is in an audible range and indicates a state where the torque is large and switching noise of the motor 400 is likely to be generated due to the torque. The map Gn3 is used when the carrier frequency fc is high and indicates a state where noise of the motor 400 is likely to be generated at a certain rotational speed ωr. Each of the maps prestores the state where noise and vibration of the motor 400 are likely to occur.

[0083] Upon receiving the warm-up mode command H*, the switching determiner 214 refers to the map Gn1, Gn2, or Gn3 corresponding to the carrier frequency fc, and outputs the switching signal Ch to the dq-axis converter 232 and the gate signal generator 234 based on the torque command T* and the rotational speed ωr when the torque command and the rotational speed do not correspond to the range Np in which the switching signal Ch is not output. If no warm-up mode command H* is received, the switching determiner 214 does not output the switching signal Ch. Consequently, the generation of noise and vibration of the motor 400 can be avoided. Although an example in which the switching determiner 214 receives the warm-up mode command H* has been described, the controller 200 may receive the warm-up mode command H* and operate upon receiving the warm-up mode command H*. Besides the warm-up mode command H*, operation can be performed under various conditions as needed.

[0084] Fig. 8 is a diagram illustrating an operation example of the engine control device 1000. Fig. 8 shows a vertical axis representing temperature and a horizontal axis representing time.

[0085] The motor control device 1000 starts operation at time t0. Immediately after the start of operation, the temperature It of the inverter 100 and the temperature Mt of the motor 400 are low. Thereafter, a warm-up mode is set by the warm-up mode command H* at time t1. The temperature It of the inverter 100 and the temperature Mt of the motor 400, which are not close to the limiting temperature Ri and the limiting temperature Rm, respectively, cause the first temperature state S1 in which the inverter 100 and the motor 400 generate heat at the maximum. The temperatures of the inverter 100 and the motor 400 can be increased more quickly than those in a configuration not according to the present embodiment.Specifically, the carrier frequency and current setpoint that cause the maximum amount of energy loss are preferably calculated for the inverter 100, so that the temperature of the inverter 100, which has a low heat capacity, can be increased first. Consequently, the temperature R1 of the refrigerant in the inverter 100 can be quickly increased, and the refrigerant can be used as a heat source for the vehicle's air conditioning or the like.

[0086] The temperature It of inverter 100, which has approached the limiting temperature Ri at time t2, causes the second temperature state S2. In the second temperature state S2, the carrier frequency is lowered and the current setpoint is increased. Heat generation of inverter 100 is relatively suppressed, and heat generation of motor 400 is relatively increased.

[0087] The temperature Mt of the motor 400, which has approached the limiting temperature Rm at time t3, triggers the third temperature state S3. In the third temperature state S3, the current setpoint is lowered to suppress heat generation of the motor 400.

[0088] Each of the states uses the carrier frequency and current setpoint that cause the maximum amount of energy loss based on the energy margin value, so that the temperature of the inverter 100 and the motor 400 can be efficiently increased. If the inverter 100 or the motor 400 may have a temperature that exceeds the corresponding one of the limiting temperatures Ri and Rm, a known protection function is executed.

[0089] The embodiment described above enables the operating effects below to be achieved. (1) The motor control device 1000 is connected to the inverter 100, which performs power conversion between DC power and AC power, and controls the inverter 100 based on the carrier frequency fc and the current command value I* corresponding to the torque command T* to control the driving of the motor 400 using the AC power. The motor control device 1000 then includes the command value generator 213, which calculates the inverter energy margin value Wi corresponding to an energy margin of the inverter 100 up to the inverter limiting temperature Ri, which is the limiting temperature of the inverter 100, based on the detection temperature It of the inverter 100, and generates a new carrier frequency fc and a new current command value I* instead of the carrier frequency fc and the current command value I* corresponding to the inverter energy margin value Wi.To increase the temperature of the inverter 100, the carrier frequency fc and the current command value I* are changed to those generated by the command value generator 213 to control the inverter 100. Consequently, the temperature of the inverter can be efficiently increased within a range of the limiting temperature Ri. (2) A motor control method is a method of the motor control device 1000 connected to the inverter 100 that performs power conversion between DC power and AC power, and controlling the inverter 100 based on the carrier frequency fc and the current command value I* corresponding to the torque command T*, to control the driving of the motor 400 using the AC power.The motor control method then includes the steps of: calculating the inverter energy margin value Wi corresponding to an energy margin of the inverter 100 up to the inverter limiting temperature Ri, which is the limiting temperature of the inverter 100, based on the detection temperature It of the inverter 100; generating a new carrier frequency fc and a new current command value I* instead of the carrier frequency fc and the current command value I* corresponding to the inverter energy margin value Wi; and changing the carrier frequency fc and the current command value I* to those generated according to the energy margin value Wi to control the inverter 100, thereby increasing the temperature of the inverter 100. Consequently, the temperature of the inverter can be efficiently increased within a range of the limiting temperature Ri.

[0090] In the above-described embodiment, an example was described in which the warm-up controller 210 calculates the energy margin value Wi of the inverter 100 and the energy margin value Wm of the motor 400, determines the carrier frequency fc and the current command value I* in the warm-up mode based on the calculation results, and outputs the carrier frequency fc and the current command value I* to the inverter controller 230. Alternatively, only one of the energy margin value Wi of the inverter 100 and the energy margin value Wm of the motor 400 may be calculated, and the carrier frequency fc and the current command value I* in the warm-up mode may be determined based on the calculation result.That is, the present invention makes it possible to control the inverter 100 by calculating at least one of the energy margin value Wi of the inverter 100 and the energy margin value Wm of the motor 400, and determining the carrier frequency fc and the current command value I* in the warm-up mode based on a result of the calculation.

[0091] When only one calculation result of the energy margin value Wi of the inverter 100 is used, the loss calculator 211 may not include the loss reference unit 2111b, the time constant time calculator 2112b, and the loss integrator 2113b associated with calculating the loss Lm of the motor 400. The estimated temperature reference unit 2121b, the differential temperature calculator 2122b, and the limiting temperature update unit 2123b associated with updating the limiting temperature Rm of the motor 400 may also not be provided. In addition, the energy margin value calculator 2131b, the command value reference unit 2132b and the command value selector 2133b associated with calculating the energy margin value Wm of the motor 400 and determining a current command value corresponding to the energy margin value Wm may not be provided.Consequently, the temperature of the inverter 100 can be efficiently increased in the warm-up mode and used as a heat source for air conditioning and the like.

[0092] On the other hand, if only a calculation result of the energy margin value Wm of the motor 400 is used, the loss calculator 211 may not include the loss reference unit 2111a, the time constant time calculator 2112a, and the loss integrator 2113a associated with calculating the loss Li of the inverter 100. The estimated temperature reference unit 2121a, the differential temperature calculator 2122a, and the limiting temperature update unit 2123a associated with updating the limiting temperature Ri of the inverter 100 may also not be provided. In addition, the energy margin value calculator 2131a, the command value reference unit 2132a, and the command value selector 2133a associated with calculating the energy margin value Wi of the inverter 100 and determining the carrier frequency and the current command value corresponding to the energy margin value Wi may not be provided.Consequently, the temperature of the engine 400 can be efficiently increased in the warm-up mode and used as a heat source for air conditioning and the like.

[0093] The present invention is not limited to the embodiments described above, and other forms conceivable within the technical idea of ​​the present invention are also included in the scope of the present invention as long as the features of the present invention are not impaired. List of reference symbols 100 inverters 101 Temperature detector 200 controllers 210 Warm-up Controller 211 Loss Calculator 212 Corrector for restrictive temperatures 213 Setpoint generator 214 switching determiner 220 carrier frequency generator 230 Inverter Controller 231 Current command generator 232 dq-axis converters 233 UVW coordinate converter 234 Gate signal generator 300 DC power supply 400 engine 401 Position detector 402 Current detector 500 refrigerants 502 Temperature Detector 1000 engine control device 2111a, 2111b Loss Reference Unit 2112a, 2112b time constant calculator 2113a, 2113b Loss integrator 2121a, 2121b Estimated temperature reference unit 2122a, 2122b Differential temperature calculator 2123a, 2123b Restrictive temperature update unit 2131a, 2131b Energy Span Value Calculator 2132a, 2132b Setpoint reference unit 2133a, 2133b Setpoint selector 2134 Temperature State Determinator It, Mt detection temperature VR delay R1, R2 Refrigerant temperature H* Warm-up mode command T* Torque command ωr speed fc carrier frequency I* Current setpoint θ rotational position Ch switching signal Li, Lm loss Ri, Rm limiting temperature Wi, Wm energy range QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2021-132464 A

[0004]

Claims

[1] A motor control device connected to an inverter configured to perform power conversion between DC power and AC power, and controlling the inverter based on a carrier frequency and a current command value corresponding to a torque command to control driving of a motor using the AC power, the motor control device comprising: a setpoint generator that calculates an inverter energy margin value corresponding to an energy margin of the inverter up to an inverter-limiting temperature, which is a limiting temperature of the inverter, based on a detection temperature of the inverter, and that generates a new carrier frequency and a new current setpoint instead of the carrier frequency and the current setpoint corresponding to the inverter energy margin value, wherein the inverter is controlled by changing the carrier frequency and the current setpoint to the new carrier frequency and the new current setpoint generated by the setpoint generator to increase the temperature of the inverter. [2] An engine control device according to claim 1, further comprising: a loss calculator that calculates a loss of the inverter in a predetermined time based on the torque command, the motor speed, the current setpoint and the carrier frequency, wherein the setpoint generator calculates the inverter energy margin value based on the inverter loss obtained by the loss calculator. [3] An engine control device according to claim 2, further comprising: a limiting temperature corrector that updates the inverter limiting temperature according to a deviation when the deviation occurs between an estimated temperature estimated based on the loss of the inverter and the detection temperature of the inverter. [4] Engine control device according to claim 3, wherein the setpoint generator contains a temperature state determiner that determines a temperature state of the inverter, the temperature state determiner determines a first temperature state when the inverter has a temperature that is not close to the inverter-limiting temperature, or when no deviation occurs in the estimated temperature estimated based on the loss of the inverter, and the setpoint generator in the first temperature state generates the carrier frequency with a high value and the current setpoint with a low value. [5] The motor control device according to claim 4, wherein the temperature condition determiner determines a second temperature condition when the inverter has a temperature close to the inverter-limiting temperature or when a deviation occurs in the estimated temperature estimated based on the loss of the inverter, and the command value generator generates the current command value with a high value and the carrier frequency with a low value in the second temperature condition. [6] The motor control device according to claim 5, wherein the command value generator calculates a motor energy margin value corresponding to an energy margin of the motor up to a motor limiting temperature, which is a limiting temperature of the motor, based on a detection temperature of the motor, and generates the new current command value according to the motor energy margin value. [7] Engine control device according to claim 6, wherein the limiting temperature corrector updates the motor limiting temperature according to a deviation when the deviation occurs between the estimated temperature based on the loss of the motor and the detection temperature of the motor, the temperature state determiner determines a third temperature state when the engine has a temperature close to the engine-limiting temperature or when a deviation occurs in the estimated temperature estimated based on the loss of the engine, and the setpoint generator generates the new current setpoint in the third temperature state with a value, the value being lower than a value in a state other than the third temperature state. [8] The motor control device according to claim 7, wherein the temperature condition determiner determines the first temperature condition in which the inverter has a temperature not close to the inverter-limiting temperature and the motor has a temperature not close to the motor-limiting temperature, determines the second temperature condition in which the inverter has a temperature close to the inverter-limiting temperature, and determines the third temperature condition in which the motor has a temperature close to the motor-limiting temperature. [9] Engine control device according to claim 8, wherein the temperature condition determiner not only determines whether the inverter has a temperature that satisfies a first condition corresponding to the inverter-limiting temperature, but also whether the motor has a temperature that satisfies a second condition corresponding to the motor-limiting temperature, the temperature condition determiner determines the first temperature condition if the inverter has a temperature that does not meet the first condition and the motor has a temperature that does not meet the second condition, the temperature state determiner determines the second temperature state if the inverter has a temperature that satisfies the first condition, the temperature state determiner determines the third temperature state when the engine has a temperature that satisfies the second condition, and the temperature state determiner, when the inverter has a temperature satisfying the first condition and the motor has a temperature satisfying the second condition, determines the second temperature state or the third temperature state by determining which of the temperature of the inverter and the temperature of the motor is closer to the corresponding one of the inverter-limiting temperature and the motor-limiting temperature. [10] Engine control device according to one of claims 1 to 9, further comprising: a switching determiner that determines whether to allow a change in the carrier frequency and the current command value newly generated by the command value generator based on the torque command, the motor speed and the carrier frequency, where, when the switching determiner determines the admissibility of the change, the current setpoint and the carrier frequency newly generated by the setpoint generator are used. [11] The motor control device according to any one of claims 1 to 9, wherein the inverter is controlled by changing the current command value and the carrier frequency to the current command value and the carrier frequency newly generated by the command value generator when a warm-up mode command instructing warm-up is received. [12] A motor control device according to any one of claims 1 to 9, wherein the inverter is controlled by changing the current command value and the carrier frequency to the current command value and the carrier frequency newly generated by the command value generator during the regenerative driving of the motor. [13] A motor control method for a motor control device connected to an inverter configured to perform power conversion between DC power and AC power, and controlling the inverter based on a carrier frequency and a current command value corresponding to a torque command to control driving of a motor using the AC power, the motor control method comprising: Calculating an inverter energy margin value corresponding to an energy margin of the inverter up to an inverter limiting temperature, which is a limiting temperature of the inverter, based on a detection temperature of the inverter; Generating a new carrier frequency and a new current command instead of the carrier frequency and current command according to the inverter energy margin value; and Control the inverter by changing the carrier frequency and current command value to the carrier frequency and current command value newly generated according to the inverter energy margin value to increase the temperature of the inverter.

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